Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concerns.. As per your complain Melasma leads to dark brownish to blackish patches on face and is most commonly due to hormonal imbalances.. As you have used Hydroquinone and Tretinoin containing creams it is true that they reduce the pigmentation quickly but the drawback is the relapse of pigmentation once their use is stopped.. I would suggest you to use other safer depigmenting agents that will help in reducing dark spots.. You can start washing your face with Salicylic acid containing facewash.. You can apply creams containing Kojic acid, Glycolic acid and arbutin.. You can also apply Vitamin E and C containing creams.. Take Vitamin C supplements and also take more of green leafy vegetables and fresh fruits in diet.. You can also exfoliate your skin twice a week with a gentle scrub.. Drink plenty of water.. Limit sun exposure and always apply sunscreen lotion.. You can also go for photofacial, microdermabrasion and chemical peeling.. Hope this information helps.. Thanks and regards. Dr.Honey Nandwani Arora.